This is the switch for the thermo timer cold start injector.  It sits in the main thermostat housing.  1977 year models onward Shadow II, Silver Wraith II Spirit, Spur, Mulsanne,...

This is the radiator Cap Seal - On the cap for 6 cylinder models only.  1946-1955 Mk-6, R-Type, Silver Dawn, Silver Wraith 1955-1959 Silver Cloud I & S-1

This is the thermostat for the early cars with the 6 Cylinder engines.  Opens at 78 degrees. 1946-1955 Mk-6, R-type, Silver Dawn, Silver Wraith  1956-1959 Silver Cloud I & S-series 1...

This is the gasket for the coolant thermostat housing. The part was originally EB3952. It has been superseded by RH12900  1945-1959 6 Cylinder Models